OFFSET
0,2
COMMENTS
The first negative term is the 66th.
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
I. Jensen, Table of n, a(n) for n = 0..171 (from Jensen link below)
J. W. Essam et al., Analysis of extended series for bond percolation on the directed square lattice, Phys. Rev. B 33 (1986), 1982-1986.
J. W. Essam, A. J. Guttmann and K. De'Bell, On two-dimensional directed percolation, J. Phys. A 21 (1988), 3815-3832.
I. Jensen, More terms
Iwan Jensen, Anthony J. Guttmann, Series expansions of the percolation probability for directed square and honeycomb lattices, J. Phys. A 28 (1995), no. 17, 4813-4833.
CROSSREFS
KEYWORD
sign
AUTHOR
STATUS
approved